The present invention relates to beverage dispensing systems in general, and in particular to an improved post-mix beverage dispensing system that always dispenses chilled beverages irrespective of the time lapse between dispensing of beverages.
In a typical post-mix beverage dispensing system, carbonated water (soda) and various flavored syrups flow through individual circuits of stainless steel tubing embedded in a cost aluminum cold plate. Cooling of the syrups and soda in the cold plate is accomplished by maintaining ice on the surface of the plate. One means of delivering ice to and maintaining ice on the surface of a cold plate is described in U.S. Pat. No. 4,300,359, in which ice from a hopper of an ice dispenser is conveyed by gravity to an enclosure in which a cold plate is positioned, so that a supply or ice is always maintained around the cold plate.
Chilled syrups leaving the cold plate are conveyed through insulated tubes directly to individual ones of a plurality of dispensing faucets. On the other hand, chilled soda leaving the cold plate is introduced into a manifold, typically of insulated stainless steel, that distributes soda to each faucet through individual outlet taps. When a faucet is actuated to dispense a beverage, soda water and a selected flavored syrup flow to the faucet and mix as they are dispensed, usually in a ratio of 5 parts soda to 1 part syrup.
As long as beverages are relatively frequently dispensed, they flow from the faucets in a chilled state. However, when the system stands idle for a period of time, although the syrup and soda within the cold plate itself are maintained cold, the first beverage dispensed after an idle period comes from the delivery lines and soda manifold. This product warms up as it stands, due to absorption of heat from the surrounding ambient, and can no longer be cooled. The first drink drawn after an idle period will therefore be warmer than the usually desired 40.degree. F., resulting in excessive foaming and a generally undesirable drink.